Network Troubleshooting/Protocol Analyzer Tools

Wireshark is the most popular network troubleshooting tool - protocol analyzer as they call themselves. It is free and open source. It can be used for network analysis, troubleshooting, protocol analysis and education. 

What is DHCP?

DHCP stands for Dynamic Host Control Protocol. In order to describe DHCP we need to first describe BOOTP, which it evolved from. BOOTP protocol was used for assigning IP addresses to diskless workstations. It was not a dynamic protocol, i.e. it was not assigning the IP addresses dynamically. It was pulling the addresses from a static BOOTP file which was maintained by the network administrator. Unlike the BOOTP, DHCP helps you to assign the IP addresses dynamically to the network computers or any devices that needs IP address to connect to the internet. The IP addresses delivered by the DHCP are delivered from a pool which the network administrator created on the DHCP server. These IP addresses can be assigned permanently or temporarily. DHCP removes a great part of the drudgery that would be included in manual assignments of IP addresses. As well as the specific DHCP appliances, most network operating systems provide DHCP service.